The invention relates to a method for increasing inking resolution in an ink-mosaic recording device with a recording head having a number of piezoelectric transducers arranged in series. Through a piezoelectric deformation of the transducers, dropwise recording fluid is directionally ejected onto a recording-carrier. Furthermore, the invention relates to an arrangement for carrying out this method. Ink-mosaic recording devices are, for example, rod-shaped transducers arranged in parallel with one another and lying opposite a nozzle-plate, as is known from German Patent Specification No. 25 27 647, incorporated herein by reference, and in the following will be designated in brief as comb-recorders. The rod-shaped transducers may in this connection be attached to one another a one side or on both sides through a stem or common base portion. It is to be further understood that the recording devices indicated in the earlier German patent application No. P 33 20 441, incorporated herein by reference, having a pre-tensioned comb closed on both sides through a stem may also be employed. Furthermore, the recording head for the ink-mosaic recording device may also contain a channel-matrix indicated in the earlier German Patent Application No. P 33 06 098, incorporated herein by reference, with or without a matrix of holes. It is to be further assumed that the ink-mosaic recording device may be constructed in similar manner as the device known from the German Published Specification No. 25 43 451, incorporated herein by reference, in which a series of ink channels are to be guided radially from piezoelectric pressure chambers to ink nozzles.
In the case of all of these ink-mosaic recording devices, primarily an inking resolution of approximately four drops of ink per millimeter is attained. For an improvement of the type character, about 10 of such ink-drops would be desirable. A known solution of this problem with a comb-recorder provides, for example, for arranging several piezoelectric combs offset to one another in a direction of paper transport. This requires, however, a doubling of the electronics, and under certain circumstances e.g. insufficient paper feed accuracy may also lead to a distortion in the type character. A diminishing of the spacing between the piezoelectric transducers, for example with the comb-recorder, increases, apart from production difficulties, appreciably the danger of hydraulic coupling between the transducers.